Ellipsograph



Oct. 26, 1948.

K. B. .NOBLE 2,452,484

ELLIPSOGRAPH Filed April l5, 1944 w33 36 236/7 646` .a5 r5.2

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Patented Oct. 26, 1948 UNITED STATES lPATENT OFFICE.

l ELLIPsoGRAPH Kenneth B. Noble, Hartford, Conn.

Application April 15, 1944, Serial No. 531,149

4 Claims. 1 This invention `relates to improvements ellipsographs.

One object of this invention is to provide an improved. ellipsograph ofsimple construction inl whereby ellipses can be completely scribedwithout employing any supplemental devi-ce.

Another Iobject of this invention is to provide an improved ellipsographformed of simple elements readily manufactured to produce an eiiicientconstruction at moderate cost.

With the above and other dbjects in view; as will appear to thoseskilled in the art `from the present disclosure, this invention includesall features in the said disclosure which are novel over the prior art.

In the accompanying drawings forming 'part of the present disclosure, inwhich certainways of carrying out the invention are shown forillustrative purposes:

Fig. 1 is a perspective view of an ellipsograph made in accordance withthe present invention;

Fig. 2l is a top plan View of the track-construction portion of theellipsograph, with one of the track-members shown in detached butadjacent position;

Fig. 3 is a sectional view on an enlarged scale, taken on line 3-3 ofFig. 2;

Fig. 4 is a top plan view of the scriber-bar construction;

Fig. 5 is a side elevation of a frag-mental endportion yof Fig. 4;

Fig. 6 is a front elevation of one of the scriber- I bar pivot-members;

Fig. 7 is a perspective view of the slide of Fig. 6; Fig. 8 is aperspective View of the scriber-hold- Fig. 9 is a front elevation yof apencil-scriber;

Fig. 10 is a side elevation of a pen-scriber;

Fig. 11 is a side elevation ofthe detached trackmember forming the upperpart of Fig. 2;

Fig. l2 is an end view of Fig. 11;

Fig. 13 is a front elevation of the track-member shown in Fig. 2;

Fig. 14 is a view similar to Fig. 13 of a Ashorter track-member; and

Fig. 15 is a view similar to Fig. 13 of a longer track-member adapted tobe removably secured to the center-hub in three different longitudinalpositions.

Referring to the drawings, the ellipsograph 2|) includes arelatively-fixed track-construction or -means 2| and arelatively-movable scriber-c-onstruction or -means 22. Thetrack-construction 2| includes a center-hub 23 having transverse slots24 and 25 extending entirely therealoss at horizontal right angles toone another, each of said slots being of rectangular cross-sectionalform of the same width and depth and of a size to have a neatsliding-fit with any of the track-members or -bars 26, 21 and 28.Spring-pressed latches or locks 29, 30, 3| and 32 serve to removablysecure the track-bars in their proper positions in the slots 24 and 25of the center-hub 23.

Each of the four latches includes a latch-bolt 33 (Fig. 3)longitudinally slidable in a 'hole 34 in the center-hub 23 and normallypressed inward by a c-oil-spring 35 to cause the inner end 36 of thebolt to be engaged in one of the latching-recesses or -sockets 31 of thetrack-bars, the spring 35 having vone of its ends pressing against theflange kor washer 38 on the bolt, and having its other end pressingagainstl the washer 39, which is i'lxedly secured in an annular shallowrecess 4|] in the center-hub 23. The shank 4| of the latch-bolt 33extends through a latchoperating member 42 which is freely -pivotedthereon, and is held in properly-adjusted position [by suitableadjustment of a nut 43 upon the threaded end of the shank 4|. A slot 44in the end of the latch-bolt 33 serves to permit of holding the boltagainst rotation by a screw driver while the nut 43 is being forciblyscrewed onto its desired adjusted position.

The latch-bolt 33 can be operated to release its engagement with any ofthe track-members by engaging the upper end-portion 45 of thelatch-operating member 42 (Fig. 3) with a finger or fingernail andpressing it to swing it downward toward the broken-line position shownin Fig. 3, to cause the lower end-portion 46 of the operating-member 42to ride along the cylindrical surface 41 of the center-hub 23, to thusproduce a camming action to force the latch-bolt 33 to movelongitudinally of itself -outward against the action of the spring 35-untl the inner end 36 of .the latch-bolt 33 is drawn back at least 'asfar as the side-face 48 of the track-bar in which the latching-recess 31is formed, whereupon the tra-ck-bar can be withdrawn from its locationin the slot 24 or slot 25 in which it may be located 'in the center-hub23. The combined action lof the spring 35 and the cam-surface 41restores the parts 4'2 and 33 to the original locking position.

T-o replace a track-bar in its position in a slot in the center-hub 23,as for example in the case of the track-bar 26 shown in Fig. 2, it canbe moved longitudinally from its position shown in Fig. 2 into the slot24 until the cam-face 49 of the track-bar engages the end 33 of thelatch- 'bolt 33 of the latch 29, to thus force the end 36 backward asfar as the face 48 of the track-bar 26, thus permitting the track-bar 26to be pushed longitudinally inward to its proper position, whereupon thebolt-end 36 is snapped automatically into the recess 31 by the spring35. Of course, the track-bar 26 can be inserted in its latched or lockedposition by movement in any direction as, for example, bymoving ittransversely of the slot 24, but inthis case it is necessary to operatethe latch-operating member 42 by pressing it with a iinger, aspreviously described, in order to retract the latch-bolt 33.

The track-bar 21 (Figs. 2 and 13) has latching-recesses 31 in itsopposite sides to be engaged by the latches 30 and 32 when the track-bar21 is moved into the slot 25 of the center-hub 23 while thelatch-operating members 42 are held in unlatching position, after whichthey are moved to latching position to permit the latch-bolt ends 36 toengage in the latching-recesses 31, as previously described with regardto track-bar 26. The track-bar 28 is identical with track-bar 26 and,therefore, is removable and replaceable in its latched position in thecenter-hub in the same manner as previously described concerning thetrack-bar 26. j

It will be noted that the track-bar 21 extends horizontally clear acrossthe center-hub 23, whereas the two track-bars 26 and 28 when in theirassembled position, as in Fig, 1, will abut against the oppositeside-faces of the track-bar 21.

Each of the track-bars 26 and 28 is provided with a track-way portion 58which, together with the track-way slots formed inthe track-bar 21,together constitute one track-way 52 of the ellipsograph. Anothertrack-way 53 in the trackbar 21 forms the other track-way extending atright angles to the iirst track-way 52. Each track-bar 26 and 28 has arecess 54 in which is secured a footor support-memberl 55 which may, forexample, be of soft rubber or may be a needlepoint member. And thetrack-member 21 has two of these feet 55 (Fig. 13) adjacent its oppositeends. The feet 55 are of a length to support the track-constructionportion 2| of the ellipsograph upon four feet 55, with thebottom-surface of the center-hub 23 preferably spaced upfsornewhat fromthe surface on which the ellipse is to be able scriber orscribing-member such, for ex` ample, as the pencil-scriber 58 shown inFig .9 or the pen-scriber 68 shown in Figi 10.

' Each pivot-slide 51 includes a slide-bar or slide 6| shaped to have aneat sliding-fit in the various trackways. A pivot-disk 62 is connectedto the slide-bar 6| by means of a` screw 63 threaded into the slide andhaving its countersunk head 64 serving to pivot the disk 82 relativelyto the slide-bar 6| A cap-disk 65 is secured to the disk 62 by thescrews 66. A recess 61, which extends entirely across the lower face ofthe cap-disk 65, in conjunction with the upper face of the disk 62constitutes a channel or passage through which the scriber-bar 56 isslidable for adjustment, it being secured in any desired position ofadjustment by means of the screw 68 mounted in the disk 65 by screwingit downward to clamp the scriber-bar 56 in its desired position ofadjustment. A recess or clitaway-portion 65 (Fig. 4)

in the 'cap-disk 65' permits of visual observation of the graduations ofthe scale on the upper face of the scriber-bar 56, the rear face 18 ofthe slot 69 intersecting the pivot-center of the scriber-bar 56 and thedisks 65 and 62, thus serving as the points of observation indetermining the distance between the pivots of the two pivot-slides 51.The scriberholder or -head 58 has a cross-slot 1| in which one end ofthe scrber-bar 56 is clamped in position by means of a screw 12. Thescriber-holder 58 has a cylindrical hole 13 which extends verticallydownward, and in which the cylindrical surface 14 of the pencil-scriber58, and the cylindrical surface 15 of the pen-scriber 6D have a neatsliding-fit. When the pen-scriber 68 is to be used, the slot 16 providesa clearance-way to accommodate the shank 11 of the adjustingscrew 18. Ifdesired, the scriber-member used may iioat by sliding up and down in thecylindrical hole 13, or it may be iirmly secured in a given positiontherein by means of a clampingscrew 19.

With the distance relations between the center of the hole 13 of thescriber-holder and the pivotcenter of each of the pivot-slides 51suitable to scribe a given ellipse, in accordance with wellknownprinciples, the clamping-screws 68 are clamped down to hold thepivot-slides 51 in the desired selected positional relations with regardto the scriber-bar 56. Assuming the size of the ellipse to be drawn tobelarge enough so .that as the scriber, such, for example, as thepencilscriber 53, can pass beyond the ends of all the track-bars, it ismerely necessary to move the scriber-member in a direction transverse ofthe scriber-bar 56 to scribe an ellipse, the pivotslide 51 mounted inthe trackway 52 moving back and forth along the trackway while the otherpivot-slide 51 moves back and forth along the other trackway 53 in awell-known way. If, however, the size of the ellipse to be scribed issuch that the track-bars 26 and 28 are too long to permit of the passageof the scriber past these track-bars, then before the scriber reaches aposition near the bar 26, the latch 28 is actuated to release the bar26, which is thereupon removed and the scriber is continued initselliptical path until it passes beyond the place which had been occupiedby the bar 26, whereupon the latter is replaced in its original positionin the center-hub 23 in a manner previously described, and the scriberis continued in its elliptical rotation past the right end of thetrack-bar 21, whereupon the track-bar 28 is removed from its position inthe center-hub 23 in the same fashion as previously described concerningthe trackbar 26, until the scriber has been caused to travel past theposition previously occupied by the trackbar 28, whereupon the latter isvreplaced in its position shown in Fig. 1 and the scriber is continuedin its rotation until it completes the ellipse at the position fromwhich it originally started.

If it happens that the track-bar 21 is too long to permit of thescribing of a given desired ellipse, then a shorter track-bar, such asthe track-bar 88 of Fig. 14 is substituted in place of the trackbar 21.The track-bar 8| of Fig. 15 could be employed in place of either of thetrack-bars 21 or 88 of Figs. 13 and 14. If track-bar 8| of Fig. 15 werein position in the center-hub 23 in place of the track-bar 21, and itwere desired to draw an ellipse smaller than could be drawn with thetrack-bar 21 in place, for example, then it would not be necessary toremove the track-bar 8| to substitute the track-bar 80 of Fig. 14 inplace thereof, but it would only be necessary to unlatch the two latches30 and 32 and shift the track-bar 8| longitudinally of itself to bringthe locking-holes 3l' adjacent one of its ends in position to be latchedor locked by the latches 3D and 32, in which position the scriber couldbe moved past that end of-the track-bar 8|. When the scriber-member hadbeen swung around to near the other end of the track-bar 8|, then thetrack-bar 8| could again be unlatched and slid back longitudinally ofitself in the opposite direction to bring the holes 31 adjacent suchother end of the bar in latching position with the latches 3|! and 32,whereupon the scriber could be passed beyond this end of the bar 8| tomake the ellipse in the manner more fully previously described.

In making ellipses with any of the constructions previously described,it will be noted that the outside-ends of all track-bars are providedwith slots 82 which extend downwardly through the outer end-portion ofeach outer end of each track-member, to provide means by which the eyemay readily align the track-ways with the pair of cross-linescustomarily drawn by draftsmen, which lines pass through the center ofthe ellipse that is to be drawn.

The cross-sectional contour of the track-way is free of sharp edges andwith the distance between the outer edges of the track-way, smaller thanthe maximum distance across the inner portion of the track-way, thusproviding a smooth track-way slot which will hold the slides 6| fromrising up out of the slots and also, due to the absence of sharp edges,avoiding any binding action,` thus bringing about very smooth action inthe scribing of the ellipse with consequent perfection and speed ofdrawing of the latter. The track-bars are preferably made by extrudingor drawing them to nished cross-sectional shape and size, thus makingthe shape and size of the trackway absolutely uniform. They can besatisfactorily extruded or drawn from brass, for example.

While the particular scribing means illustrated and described heretoforeconsists of means for drawing ellipses by pencil or ink, it will beappreciated that any suitable scribing-means may be employed with thisdevice, such as gasket cutters, glass cutters, or other instruments, tomark or cut shapes in the form of an ellipse.

One can readily acquire sufcient skill in the removal and replacement cithe track-bars 26 and 28 so that an ellipse can be scribed quickly in acontinuous motion and in one uninterrupted line to completion.

The invention may be carried out in other specic ways than those hereinset forth without departing from the spirit and essentialcharacteristics of the invention, and the present embodiments are,therefore, to be considered in all respects as illustrative and notrestrictive, and all changes coming within the meaning and equivalencyrange of the appended claims are intended to be embraced therein.

I claim:

1. An ellipsograph including: a center hub; track-members formingtrack-means which is provided with two trackways extending transverselyof one another; at least one of said trackmembers being removablysecurable to said center hub by means of a latch which is spring-pressedto latched position and which is provided with an operating-memberextending upwardly above the top of the ellipsograph adjacent saidoperating member; and scribing means including slides slidable in saidtrackways for scribing an ellipse.

2. An ellipsograph including: a center hub; track-members formingtrack-means which is provided with two trackways extending transverselyof one another; at least one of said trackmembers being removablysecurable to said center hub by a latch having an operating memberextending upwardly above the top of the ellipsograph adjacent saidoperating-member; and scribing means including slides slidable in saidtrackways for scribing an ellipse.

3. An ellipsograph including: a center hub; track-members formingtrack-means which is provided with two trackways extending transverselyof one another; at least one of said trackmembers being removablysecurable to said center hub by means of a latch which is spring-pressedto latched position; said removable track-member having a cam-faceadjacent one end for forcing the latch back against the action of thespring; and scribing means including slides slidable in said trackwaysfor scribing an ellipse.

4. An ellipsograph including: a center-hub; a first track-memberprovided with a rst trackway and with a plurality of spaced-aparttrackway slots extending transversely of said first trackway and beingremovably securable to said center-hub in diierent longitudinalpositions; second and third track-members removably securable to saidcenter-hub at opposite sides of said first track-member and providing asecond trackway extending transversely of said rst trackway; one of saidtrackway-slots being in alignment with said second trackway, in each ofthe said different longitudinal positions of said track members formingtrack-means which is first track-member; and scribing means includingslides slidable in said trackways for scribing an ellipse.

KENNETH B. NOBLE.

REFERENCES CITED The following references are of record in the ile ofthis patent:

UNITED STATES PATENTS Number Name Date 246,174 McC-omb Aug. 23, 1881302,247 Harwood July 22, 1884 932,768 Dexter Aug. 31, 1909 1,029,515Schreiber June 11, 1912 2,326,412 Taylor Aug. l0, 1943 FOREIGN PATENTSNumber Country Date 49,611 Switzerland Sept. 14, 1909 182,479 GermanyMar. 22, 1907

